1. Field of the Invention
The present invention relates to an ink jet recording head capable of ejecting a droplet of ink or the like and a method of producing an ink jet recording head.
2. Description of the Related Art
An ink jet recording apparatus is generally formed of an ink jet recording head provided with multiple ejection orifices and a carriage for causing the ink jet recording head to scan the top of a recording medium. In addition, the apparatus performs recording by causing nozzles to eject ink droplets while moving the ink jet recording head on the recording medium.
In an ink jet recording mode, the ink droplets to be ejected from the nozzles are classified into a main droplet and a sub-droplet produced as a result of separation from the main droplet. The sub-droplet is a small ink droplet and ejected at a slow speed as compared with the main droplet. Accordingly, the sub-droplet generally impinges on a position on the recording medium different from that of the main droplet, and the difference may be responsible for a reduction in the quality of a recorded image.
In order that such a displacement between the positions on which the main droplet and the sub-droplet impinge may be suppressed to a low level, such an approach as described below has been conventionally adopted. A distance between an ejection orifice surface at which each ejection orifice of the ink jet recording head is positioned and the recording medium is shortened, or the speed at which a droplet is ejected is increased.
Meanwhile, Japanese Patent Application Laid-Open No. 2007-283720 discloses the following ink jet recording head. The directions in which a main droplet and a sub-droplet are ejected differ from each other in relation to a relative movement direction between an ink jet recording head and a recording medium. In an ink jet recording apparatus of Japanese Patent Application Laid-Open No. 2007-283720 described in the foregoing, the ink jet recording head is mounted at such a position as to be relatively movable with respect to the recording medium, and its ejection orifice surface is tilted toward the relative movement direction of the ink jet recording head with reference to the recording medium. The apparatus is characterized in that the direction in which the main droplet is ejected is tilted by the tilt so that a displacement between the positions on which the main droplet and the sub-droplet impinge may be suppressed.
In addition, Japanese Patent Translation Publication No. 2007-514201 discloses a method of reducing damage to the shape of a nozzle ejection orifice that occurs at the time of the wiping of ink, the method including forming a recess having a curved surface in a resin by photolithography and forming the ejection orifice in the curved surface.